High-Voltage Insulation Techniques for New Energy PCBA

In the field of new energy power electronics, insulation failure in PCBA can lead to catastrophic consequences. This article presents three typical failure cases to highlight the key technical aspects of high-voltage insulation treatment.

1. Material Selection Iteration

In the early stages of an onboard charger project, conventional FR-4 material was used. After 200 hours of operation at 850V, carbonization occurred on the substrate. The material was then replaced with a ceramic-filled composite recommended by PCBGOGO, which extended the service life to over 5000 hours under the same test conditions. Key parameter comparison:

• CTI value: FR-4 (175V) → Ceramic-based (600V)

• Arc resistance: increased from 3 seconds to 180 seconds

2. Precision in Process Control

In conformal coating processes, traditional spray methods often result in insufficient edge coverage. By introducing PCBGOGO’s vacuum impregnation process:

• Coating thickness deviation reduced from ±30μm to ±5μm

• Pinhole defect rate dropped by 92%

In a PCBA project for an energy storage system, thermal cycling tests revealed stress cracks between the coating and components. The solution included:

• Switching to a modified silicone resin with a lower elastic modulus

• Adding a plasma surface treatment step

3. Testing and Validation Pitfalls

A common industry mistake is relying solely on static withstand voltage testing. Real-world cases show that insulation failure is more likely under dynamic conditions. Recommended testing approach includes:

• Superimposed thermal shock (-40℃ to 125℃)

• Vibration conditions (5–500Hz)

• Continuous monitoring of partial discharge levels

PCBGOGO has adopted infrared thermography in recent R&D efforts to pinpoint insulation weak spots in real time. In one customer’s BMS project, this technique helped reduce early failure rates by 67%.

High-voltage insulation requires a comprehensive control system—from material selection to failure analysis. We welcome further discussion and collaboration on practical engineering cases.